Medical GUI - Change default body color to improve contrast

[amsteadrayle]

When merged this pull request will:

• Change default undamaged body image colors to improve contrast

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[amsteadrayle]

I recently made this change in my own settings and I think it's simply better than the current defaults. Currently, it can be difficult to tell the difference between an uninjured and slightly injured body part, both at a glance and under close inspection. The new color makes the difference completely clear, and helps to quickly identify and ignore uninjured body parts.

This also combines well with #9471, as seen in this video.